Electrical induction apparatus



E.D.TREANOR ELECTRI CAL INDUCTI ON APPARATUS Feb. 3, 1925- 1,524,762

Filed May 5, 1922 Inventor-r Edward DT-ean OT,

yW ZM H is Attorn ey.

Patented Feb. 3, 192 5.

UNITED STATES 'PATENT or Inca.

EDWARD D. W03 01 PITTSFIELD, MASSACHUSETTS, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

- :smtcrmcan mnuc'rron arrana'rus.

Application filed May 5,

To all whom-itmag cmwem:

Be it known that I, EDWARD D. TREANOR, a citizen of. the United States, residing at 'Pittsfield, in the county of Berkshire, State ofM-assachusetts, have invented certain new and useful Improvements in Electrical Induction Apparatus, of'which the following is a specification.

My invention relates to electrical induction apparatus which is cooled by immersion in a coolingand insulating liquid, such as I oil, contained in a surrounding casing.

insulating liquid.

It is customary to cool and insulate electrical induction apparatus, suchv as transformers, by immersion in 'a cooling and insulating liquid contained in a surrounding casing. The liquid surrounding the apparatus becomes heated during operation of the apparatus and its insulating roperties would very probably be impaired y oxidation or absorption of moisture if it were to come into contact with air. This is commonly prevented by filling the a paratus compartment with liquid to exclu c all air, the expansion and contraction of the liquid due to varying temperature taking place through a passage, leading to a separate artially filled expansion chamber rovided or this purpose. The general. 0 ject of the "invention is to provide an improved casing with an expansion chamber for electrical apparatus immersed in a cooling and The advantages of the invention will appear from the following description of one embodiment thereof taken in connection with the accompanying drawing which shows a transformer enclosed in a casing constructed in accordance with the inven- 1n section to reveal its construction.

In this particular embodiment of the in vention, a casing 1 is divided by two diaphragms or partitions 2 and 3 into an upper compartment 4, a central compartment 5 and a lowercompartment 6. The central come partment 5 contains a piece of electrical apparatus shown here as a tranformer 7. This central or transformer compartment 5 communicates with the lower compartment 6 throu h a pipe 8 provided with a valve 9 and 51c lower com ment 6 preferably communicates with e upper compartment 4 through another pig: valve 11. Acoew'to valve 9 may be had 10 provided with a 1922. Serial mi: 558,828.

through a hole normally closed by a plug 12 in the casing 1. With the valve 11 closed and the valve 9 open, the compartment 5 containing the transformer may be filled with oil or other insulating and cooling liquid through an opening in the upper diaphragm 2, which opening is then closed by the plug 13, enough liquid having passed through the pipe 8 into the lower compartment 6 to create air pressure in this compartment suflicient to balance the pressure of the liquid in the, central compartment 5. The pipe 8 should extend well down into the lower compartment 6 so that its lower end will be below the surface of the liquid in this compartment at all times. Expansion and contraction of the liquid in the central or transformer compartment 5 is cared for by an interchange of liquid through the opening 8 between this compartment and the lower expansion compartment 6, the elasticity of the 'air in the expansion compartment and in the pipe 10 permitting the variations in the quantity of liquid in this compartment. An inert gas, such as nitrogen may be used, if desired, in the expansion compartment instead ofair. It will be noted that liquid transferred by expansion from the transformer compartment to the expansion compartment is always from the lower portion of the transformer compartment and therefore always cool so that only cool liquid is exposed to the air in the expansion compartment. Liquid heated by the transformer during its operation rises by convection to the upper part of the transformer compartment 5 where there is no air to cause possible contamination. Leakage of air into the transformer compartment 5 may be prevented by sufficient gas pressure in the expansion compartment 6. This gas pressuremay be of such value that in case of a leak in the upper diaphragm 2 there would be a flow of liquid out of the transof air into .valve 9 then reopened. Atinos sure on the surface of the liqui phragm 2 sealed with theplug 13 'andf the pansion' compartment 6 will keepthe trans:

. former. compartment full of liquid. As

former compartment-5, air will passto and fro between the upper'or aircompartment 4 and the expansion compartment 6. -,In the preferred embodiment ,of g the invention which has been described, the air which is drawn into contact withthe 1i aid in the expansion compartment 6,v there comes from th ore always e upper orall, compartment whereit is heatedby the warm oil under l the 'upperdiaphragm-and therefore is usu'- moisture which liquid will settle to the bottom of thee]:-

casing. having three vertically ally drier than thej-0utside air surrounding the casing. This air, furthermore, can-come into contact only with cool liquid and any it may bring, to this 'cool pansion compartment where it can do no harm; It is obvious that ;wit -h' either method of operation, no precaution need be taken to make the cover of the casingv 1 above the upper or air compartment tight.

he. invention provides: a construction "which is simple, compact and efiicient and in which 'theuse ofeXternal attachment be substantiallyavoided.

%'hat I claim as new and desire to secure by Letters Patent ofkthe United States, is y 1. A casing for electrical apparatus, said casing having a compartment for the apparatus and van expansion compartment below said apparatus compartment, means providing communication between said compartments, an insulating liquid within the apparatus compartmentand extending into and partially filling the expansion compartment, a pipe extending from the expansion compartment to a pomtabove the upper part of the apparatus compartment, and

means for opening and closing said p pe.

2. A casing for electrical ratus, said ap a posed compartments, there b and between the lower and up heric pres inthe' excompartments, and an ins eing commumcation be.- tween the .jcen'tral and lower compartments r compartcentral compartment and into between the central. and lower compartmentsand" between the lower andupper compartments, and an insulating liquid within said central compartment and in which the apparatus is immersed, said liquid extending into and lower compartment.-

casing for electrical apparatus; said casing having three vertically disposed compartments, there being communication between the central and lower compartments and between the lower and upper compartments, an insulating liquid within said cens tral compartment and in which the apparatus is immersed, said liquid extending into and partially filling said lower ment, and means forv closing communication between said lower and partments;

5. In combination with electrical apparatus, means constructed to rovide three ting liquid Withinone of said compartments and in which said apparatus-is immersed, another of said compartments being partially filled with insulating liquid in communication with the liquid in said apparatus compartment, and the space abovethe liquid in said partially filled compartment munication with the third compartment.

6. In combination with electrical apparatus, means. constructed toprovide three compartments, and an insulating. liquid within one of said compartments and in which said apparatus is immersed, another of said compartments being partially filled with insulating liquid in communication with the liquid insaid apparatuscompartment, the space above the liq tially filled compartment being in communi cation with the third compartment, and said third compartment being arranged to be warmed by, heat generated by said apparatus."

partially filling said upper combeing in comcompartaid in said par- In witness-whereof, I have hereunto set my hand this 3rd day of-Ma 1922.

EDWARD D. REANOR. 

